Is your IP on a spam blocklist?
If your emails bounce or land in spam, your IP address may be listed on a DNS blocklist that mail servers check before accepting messages. This tool queries the major lists live from your browser, the same way a mail server would, and shows exactly which list flags you.
How the check works
Each blocklist publishes its data over DNS. To check an IP, you reverse its octets, append the list's zone, and query it: an answer in the 127.0.0.x range means listed, and "no such domain" means clean. This tool performs those exact queries through DNS-over-HTTPS and reports raw results — including when a list (like Spamhaus) refuses public-resolver queries, in which case we say so instead of guessing.
Listed? Here is what to do
Home connection
- Policy lists (like PSBL or UCEPROTECT) often include all residential ranges — usually harmless
- Scan your devices for malware that could be sending spam
- Restarting your router may rotate a dynamic IP
Mail server / VPS
- Confirm the server is not an open relay
- Check for compromised accounts or web forms
- Request delisting on each list's own site after fixing the cause
- Set up SPF, DKIM, and DMARC for your domain
Does a listing affect normal browsing?
Almost never. Blocklists are consulted by mail servers deciding whether to accept email, not by websites deciding whether to serve pages. If websites are blocking you, that is usually a different reputation system — often related to VPN or proxy detection, which we explain in how to hide your IP. Not sure what your current IP is? Check it here first.